The invention relates to a track-guided transport device having energy and information transmission for conveying goods, there being a transport element that includes elements for driving and track guidance.
Transport devices are used in numerous embodiments in production and storage. For example, the automobile industry has a supply system for assembly parts required on the assembly line; this system includes a track-guided telpher line which, with its own drive, can reach the individual workstations.
Containers with goods or pallets that must be loaded onto vehicles are found in high-shelf storage facilities. To this end, a lifting conveyor, for example, is provided that surmounts the difference in height between the vehicles and the spaces in the high-shelf facility. The vehicle docks, for example, at the lifting conveyor that has been allocated to it, and transfers the pallet to be stored to the conveyor. Based on the identification that the pallet bears, or that has been transmitted to the lifting conveyor by the vehicle, the conveyor can begin to sort the pallets.
The loading surface of this type of vehicle can also be configured differently, depending on the purpose of the application. For example, a transverse goods conveyor is very useful in loading and unloading containers or pallets. Of course, for assembling commissions, a container can travel with the vehicle to different stations and be loaded with parts from the stock.
It is apparent that future transport devices for executing the described, multi-faceted assignments will have to be based on technologically highly-developed partial systems constructed from system components that can be standardized for realizing economical individual solutions for the broad application spectrum. Low wear, low noise development and a small energy consumption are of high priority in the development of these systems. The basic partial systems of transport devices of this type include:
support and track-guidance elements for application-specific construction of paths of travel, or networks thereof, for transport vehicles. PA0 Autonomous, computer-guided transport vehicles having their own electrical drive and application-specific actuators and sensors and an information transmission on the vehicles. Such transport vehicles are also referred to hereinafter as transport elements. PA0 Energy-transmission devices comprising primary-side energy-transmission elements for constructing electrical energy-supply circuits, hereinafter referred to as primary circuits, that extend along the paths of travel, and secondary-side energy-transmission elements disposed on the vehicles for receiving electrical energy from the primary circuit during movement and non-movement of the vehicles. PA0 Information-transmission devices for the bidirectional exchange of movement, control and signalling information between stationary stations and vehicles, as well as between vehicles.
The application PCT/GB92/00220, on which the invention is based, discloses a contactless, inductive energy transmission to transport vehicles. In this application, a double line that forms the primary circuit is laid along the path of travel and fed with a 10-kHz current. The two conductors of the primary circuit are supported by supports comprising electrically and magnetically non-conductive material. For receiving energy, at least one E-shaped transmitter head having a ferrite core is disposed on each transport vehicle, with the middle leg of the core supporting a secondary winding and projecting deep into the space between the two conductors. The primary circuit of the double line and the secondary winding of the transmitter head are electromagnetically coupled by way of the ferrite core, so the energy required for the drive, for example, on the vehicle, that is, transport element, is transmitted from the primary circuit to the secondary winding, and from the winding, the energy is supplied via electronic control and regulation devices to the drive and further consumers on the transport element. A double line of this type possesses an electromagnetic scatter field that propagates far into the surrounding area and causes electromagnetic disturbances in neighboring signal lines, and induces eddy currents in neighboring metal parts, for example the support and track-guidance elements, particularly if they comprise steel; these eddy currents are associated with considerable energy losses. To reduce these disadvantages, therefore, it is necessary to provide a shield for the double line, which requires additional space and increases costs. The expanded scatter field of the double line also effects a high power inductance, and, because of the high frequency, it also effects a large inductive line drop that must be compensated by a correspondingly high outlay for capacitors.
GB-A-2 277 069 proposes laying a leakage waveguide along the path of travel for the bidirectional exchange of information between a stationary station and a track-guided transport element having a remote-controlled camera; the waveguide comprises a coaxial cable having an incomplete, wide-mesh, external shield. To minimize disturbances caused by interference, it is provided to localize the information transmission in the vicinity of the path of travel. In this transport device, the energy transmission is effected via a power bus comprising conventional sliding-contact rails. From FIG. 4 and page 11, lines 9-18 of the description, it ensues that signals are also transmitted via these known contact rails. Signal transmission via leakage waveguides is not described in detail.
DE-A-3 926 401 discloses a transport device for pallets and containers that are supported by magnetic fields and guided in a track. The application deals solely with a high-speed transport system that is to be installed in single-lane tunnels and is intended to assume transport tasks that were heretofore reserved for railway, long-distance automobile transport and land-plane transport. Here the moved transport elements are totally passive, so the principle applied here is relatively inflexible for the multi-faceted transport tasks of production and storage technology.
These transport devices of the state of the technology respectively realize only one of the aforementioned partial systems that are advantageous for future, flexible transport tasks in storage and production technology, such as contactless energy transmission and contactless information transmission to an autonomic transport element having its own, computer-guided drive, which is also advantageously configured as a linear drive and is combined with a magnetic support and track-guidance system. The combination of these partial systems in a transport device offers the opportunity of mechanically integrating different partial systems with respect to function, and results in structurally advantageously embodied, space-saving, low-cost, standardized system components with low wear, low operating noise and a small energy consumption.